Fundamentals and Techniques of Nonimaging

O' ; Gallagher, J. J. ; Winston, R.

The University of Chicago, Chicago, IL

关键词: Research Programs;    Solar Energy;    14 Solar Energy;    Functionals;    Illuminance;   

DOI  :  10.2172/876770
RP-ID  :  None
RP-ID  :  FG02-87ER13726
RP-ID  :  876770

美国|英语

来源: UNT Digital Library

【 摘 要 】

This is the final report describing a long term basic research program in nonimaging optics that has led to major advances in important areas, including solar energy, fiber optics, illumination techniques, light detectors, and a great many other applications. The term ''nonimaging optics'' refers to the optics of extended sources in systems for which image forming is not important, but effective and efficient collection, concentration, transport, and distribution of light energy is. Although some of the most widely known developments of the early concepts have been in the field of solar energy, a broad variety of other uses have emerged. Most important, under the auspices of this program in fundamental research in nonimaging optics established at the University of Chicago with support from the Office of Basic Energy Sciences at the Department of Energy, the field has become very dynamic, with new ideas and concepts continuing to develop, while applications of the early concepts continue to be pursued. While the subject began as part of classical geometrical optics, it has been extended subsequently to the wave optics domain. Particularly relevant to potential new research directions are recent developments in the formalism of statistical and wave optics, which may be important in understanding energy transport on the nanoscale. Nonimaging optics permits the design of optical systems that achieve the maximum possible concentration allowed by physical conservation laws. The earliest designs were constructed by optimizing the collection of the extreme rays from a source to the desired target: the so-called ''edge-ray'' principle. Later, new concentrator types were generated by placing reflectors along the flow lines of the ''vector flux'' emanating from lambertian emitters in various geometries. A few years ago, a new development occurred with the discovery that making the design edge-ray a functional of some other system parameter permits the construction of whole new classes of devices with greatly expanded capabilities compared to conventional approaches. These ''tailored edge-ray'' designs have dramatically broadened the range of geometries in which nonimaging optics can provide a significant performance improvement. Considerable progress continues to be made in furthering the incorporation of nonimaging secondaries into practical high concentration and ultra-high concentration solar collector systems. In parallel with the continuing development of nonimaging geometrical optics, our group has been working to develop an understanding of certain fundamental physical optics concepts in the same context. In particular, our study of the behavior of classical radiance in nonimaging systems, has revealed some fundamentally important new understandings that we have pursued both theoretically and experimentally. The field is still relatively new and is rapidly gaining widespread recognition because it fuels many industrial applications. Because of this, during the final years of the project, our group at Chicago has been working more closely with a team of industrial scientists from Science Applications International Corporation (SAIC) at first informally, and later more formally, beginning in 1998, under a formal program initiated by the Department of Energy and incrementally funded through this existing grant. This collaboration has been very fruitful and has led to new conceptual breakthroughs which have provided the foundation for further exciting growth. Many of these concepts are described in some detail in the report.